GZDW high-frequency switch DC screen system

Introduction to GZDW high-frequency switch DC screen system:

1、 What is GZDW DC screen system
GZDW DC screen systemIt is a power equipment used in hydraulic and thermal power plants, various substations, and other users of DC equipment to provide DC power for signal equipment, protection, automatic devices, emergency lighting, emergency power supply, and circuit breaker opening and closing operations.GZDW DC screen systemIt is an independent power source that is not affected by the generator, plant power, or system operation mode, and ensures that the backup power source - battery - continues to provide DC power to important equipment in the event of external AC interruption. The reliability of DC screens directly affects the reliability of power supply in the power system.GZDW high-frequency switch DC screen systemIt is nominal based on battery capacity, such as 65AH, 100AH. Common names: GZDW-65AH, GZDW-100AH.

IIGZDW DC screen systemthe purpose of
Widely used in hydraulic and thermal power plants, various substations, and other users who use DC equipment (such as power plants, substations, distribution stations, petrochemicals, steel, electrified railways, real estate, etc.), it provides DC power for signal equipment, protection, automatic devices, accident lighting, and circuit breaker opening and closing operations. It is also widely used as a reliable emergency power source in communication departments, computer rooms, hospitals, mines, hotels, and high-rise buildings, with a wide range of applications. The heart of the DC system is the battery, and scientific maintenance of the battery is the core work of the DC system.

IIIGZDW DC screen systemComposition of
GZDW DC screen systemIt mainly consists of two major parts. One part is the battery screen, and the other part is the DC charging screen (DC screen). A battery screen is a cabinet (800 × 600 × 2260) that can hold multiple batteries. The batteries in the battery screen are generally composed of 2V-12V batteries connected in series with 9 to 108 cells, corresponding to a voltage output of 110V or 220V. Currently, the batteries used by Huaqiang Weiye Power Supply are mainly valve regulated sealed maintenance free lead-acid batteries.GZDW DC screenIt mainly consists of cabinets, rectifier module systems, monitoring systems, insulation monitoring units, battery inspection units, switch detection units, voltage reduction units, and a series of AC input, DC output, voltage display, current display and other distribution units.

1. GZDW high-frequency switch DC screen system rectifier module:

The Huaqiang Weiye power rectifier module is a single machine module that rectifies AC power into DC power. It is usually named based on the current passing through it (such as 2A module, 5A module, 10A module, 20A module, etc.), and can also be divided into air-cooled module, independent air duct module, self cooling module, self energy air-cooled module, and self energy self cooling module according to different design concepts. It can be used in parallel with multiple units, achieving N+1 redundancy. The module output is a stable and adjustable DC voltage of 110V and 220V. The module itself has various comprehensive protection functions such as input overvoltage protection, output overvoltage protection, output current limiting protection, and output short circuit protection.

2.GZDW high-frequency switch DC screen systemmonitoring system:

The monitoring system is the control and management core of the entire DC system. Its main task is to conduct long-term automatic monitoring of various functional units and batteries in the system, obtain various operating parameters and status in the system, process them in a timely manner based on measurement data and operating status, and control the system based on this to achieve fully automatic management of the power system, ensuring its continuity and reliability of operation. There are currently two types of monitoring systems: one is button type and the other is touch screen type. The Huaqiang Weiye monitoring system provides human-machine interface operation, realizing system operation parameter display, system control operation, and system parameter setting.

3. Insulation monitoring unit:

The insulation monitoring unit of the DC system is a device that monitors the insulation condition of the DC system, and can monitor the resistance of the line to the ground drain in real time. This value can be set according to the specific situation. When the insulation of the line to ground decreases to the set value, an alarm signal will be issued. The insulation monitoring unit of Huaqiang Weiye DC system currently includes busbar insulation monitoring and branch insulation monitoring.

4. Battery inspection unit:

The battery inspection unit is a device that performs loop inspection on the online voltage status of the battery. It can detect the voltage of each battery in real time. When the voltage of a battery exceeds or falls below the set value, an alarm signal will be issued, and the monitoring system can display which battery has malfunctioned. The Huaqiang Weiye battery inspection unit is generally capable of detecting 2V-12V batteries and inspecting 1-108 batteries for environmental protection.

5. Switching quantity detection unit:

The switch quantity detection unit is a device for online detection of switch quantities and output of alarm dry nodes. For example, in the entire system, if a circuit breaker trips due to a fault or if a fuse is blown, the switch detection unit will issue an alarm signal and display which circuit breaker trips due to a fault or which fuse is blown through the monitoring system. At present, the switch quantity detection unit can collect 1-108 switch quantities and multiple passive dry node alarm outputs.

6. GZDW high-frequency switch DC screen system voltage reducing silicon chain:

The voltage reduction unit is a voltage reduction and stabilization device. It is a combined bus voltage input voltage reduction unit, which then outputs to the control bus to regulate the control bus voltage within the set range (110V or 220V). When the combined voltage changes, the voltage reduction unit automatically adjusts to ensure stable output voltage. The voltage reduction unit is also nominal based on the magnitude of the output current. There are currently two types of voltage reducing units, one is a stepped voltage reducing silicon chain, and the other is a stepless voltage reducing chopper. The stepped down silicon chain has 5 levels of voltage reduction and 7 levels of voltage reduction, with a voltage regulation point of 3.5V. This means that when the bus voltage increases or decreases by 3.5V, the stepped down silicon chain automatically adjusts the stable control bus voltage. Stepless step-down chopper is a step-down module that is smaller in size than a step-down silicon chain. It does not have a voltage regulation point, so the output voltage is more stable than a step-down silicon chain. It also has functions such as overvoltage, overcurrent, and battery over discharge. However, the current technology of stepless voltage reduction and chopping is not yet mature and often malfunctions, so the use of voltage reduction silicon chains is still widely effective.

7. Distribution unit:

The distribution unit is mainly composed of devices used in the DC screen to achieve functions such as AC input, DC output, voltage display, and current display, such as power lines, terminal blocks, AC circuit breakers, DC circuit breakers, contactors, lightning arresters, splitters, fuses, transfer switches, button switches, indicator lights, and current and voltage meters.

4、 Battery capacity selection and module configuration

The selection of battery capacity requires statistical analysis of DC load, which can be classified into regular load, accident load, and impact load based on their nature. The main loads are protection, control, automatic devices, and communication settings. Accident load refers to the load that must be powered by the DC system after a power outage, such as UPS, communication settings, etc. Impulse load refers to a high current load applied in a very short period of time, such as circuit breaker opening and closing operations. Based on the above three types of DC load statistics, the DC continuous discharge capacity under accident conditions can be calculated. Generally, in a 220KV substation DC system, two sets of batteries with a capacity of 150AH-200AH should be selected for the battery. In a 110KV substation DC system, one set of batteries with a capacity of 100AH-150AH should be selected for the battery. In a 35KV substation DC system, one set of batteries with a capacity of 50AH-100AH should be selected for the battery. The configuration of the number of modules requires that the total rated current output of all modules should be ≥ the current for frequent load and battery charging (The charging current of the battery is 0.1c-0.2c10). For example, the charging current of a 100AH battery pack is 0.1c * 100=10A. Without calculating the frequent load, selecting a module with a rated current of 5A and 2 modules can meet the charging needs of the battery. To achieve N+1 redundancy, a total of 3 5A 10A modules are selected

High frequency switch power cabinet for communication specific DC power supply systemMechanical dimensions:
Dimensions: 2260mm (height) x 800mm (width) x 600mm (depth)

Dimensions: 2260mm (height) x 800mm (width) x 800mm (depth)